This proposal calls for a new approach to assess the relationship of cultural assimilation and health among Mexican immigrants, one that departs from more conventional comparisons by considering related women and children on both sides of the border, rather than comparing immigrants and U.S. born or Non-Hispanic women in the United States. By addressing the problem in this way, we are able to deal directly with the issue of migrant selectivity. Furthermore, we argue that longitudinal data will enable us to focus on cultural assimilation as a dynamic process, allowing for change over time, which, we hypothesize, will lead to changes in health outcomes. Interviewing women in the United States and then tracing and interviewing their relatives in Mexico is a procedure that has never been tried on a large scale. The purpose of the pilot project proposed here, therefore, is to thest the feasibility of this method of data collection. Four specific objectives are: (1) To carry out short health-related interviews in two samples of Mexican women living in Chicago and Milwaukee neighborhoods; (2) To identify, trace, and interview selected siblings and sister-in-law who live in sending areas of Mexico using four alternative protocols; (3) To assess the 'yield' of each treatment or protocol and to evaluate the advantages and disadvantages of each in order to choose an optimum protocol for a larger study; (4) To assess response rates and quality of responses to the most sensitive items included in a questionnaire on maternal and child health. Findings will be sued to refine the overall project that seeks to achieve greater understanding of the relationship between health and migration and of the widely noted 'epidemiological paradox' among Mexican immigrants with new data.